jonnyapple: Yes, in a way, I agree that a super good EVF could do the job, and I like the way it could amplify the light for night shots too. But having looked though hundreds of viewfinders since I started taking pictures, I can still, today, say that I prefer an optical viewfinder. But as you say, things are going so fast that we are in for a lot of surprises in a near future.

soap: I understand that my comment got you confused. Re-reading it, I realize that for a range finder camera, that would mean that the viewfinder is the actual lens… That sounds crazy but… Who knows ?.... :oD

Oh i like the idea of the DLP chip, but the idea Pete mentions sounds rather cool too.
I like my current viewfinder, but i would definately be open to new technology, if it at some later point when more advanced, could help make my photography easier.

Pete, I like the mirror idea you mention, but instead of some electrically switched semi-transparent material, what if you could get something like a DLP chip and have it reflecting into the optical viewfinder by default, and then switched to reflect the light onto the sensor during exposure?

Bernard, I agree that no current EVF matches an optical one, but 20 years ago no digital camera matched film's quality, either. It might not happen, but I'm just saying it might.

I think it is an interesting idea. Honestly, I don't think it would take that much to implement it in todays cameras. I still would prefer my traditional eye piece view finder, but would be open to it.

The one main advantage of this would be a need to shoot in an almost completely dark room and the electronic view finder would use some sort of actual night vision technology. I'm not against manual focus, but having an auto focus mode in extremely dark settings would be a huge benefit. I know on my 105mm macro lens, you have to have good light to have the camera get a clear focus and shot of the scene. Having an electronic view finder would give it something to focus on.

bernard said:
I can't remember who made this SLR, but I remember that, many many years ago when I was using a Pentax Spotmatic, one manufacturer tried to use a static mirror which was semi transparent. It did not move at all and some of the light was used for the viewfinder. Didn't get much success though. If I remember right, the viewfinder was far too dark.

But remember today's electronics has moved a long way, I think it would be possible to have an electronic glass plate material that will change from Mirror to transparent, Anyway here is the rumor that I found again:

I can't remember who made this SLR, but I remember that, many many years ago when I was using a Pentax Spotmatic, one manufacturer tried to use a static mirror which was semi transparent. It did not move at all and some of the light was used for the viewfinder. Didn't get much success though. If I remember right, the viewfinder was far too dark.

I'm not a fan of the EVF myself, but with ISO 100K now a reality, they could be useful in low light situations. If you have the benefit of that extra sensitivity in your finder, it seems like it would be easier to focus & compose in the dark.

bernard said:
Yuck !!!… Sorry, but I believe that there is nothing like looking through an optical viewfinder. They can make the most sophisticated electronic one, I believe it will never match reality.

What they should do is the other way around: i.e. Take part of the light going through the optical viewfinder and direct it to the sensor in order to capture the image. It may not be possible today, but it will eventually.

On DpReview I read some time ago that Canon was working on an Electronic Mirror/shutter, so the mirror does not move, but is changed from being transparent to a mirror in an instant, very fast Fps, but still the feel of a normal viewfinder

Yuck !!!… Sorry, but I believe that there is nothing like looking through an optical viewfinder. They can make the most sophisticated electronic one, I believe it will never match reality.

What they should do is the other way around: i.e. Take part of the light going through the optical viewfinder and direct it to the sensor in order to capture the image. It may not be possible today, but it will eventually.

Pros:
Wide angle lens could be much smaller, no retro-focus design issues.
Lenses could be much closer to a sensor, therefore light reaching the sensor would be much stronger ergo better low light performance.
No moving parts, less mechanical failures and also very important no vibrations (especially high inertia mirror movement)
Cons:
AF as you have mentioned, though it could be much improved by integrating AF cells into to the sensor.
Electrical efficiency of all components, sensors etc, resulting heating and power consumption, it will be improved in time by using better front pane image sensitive elements (Exmore), black silicon or some other technology.
Small LCD screens resolution used in electronic viewfinders is to low today, it will could and will be improved.
Faster sensors (and better firmware) to remove nasty jello effect, I assume we will just have to wait for that to happen.

Has anyone else ever considered whether we're headed toward electronic viewfinders (EVFs) someday? It seems to me that they'll make sense once the technology advances far enough, specifically if they could get the pixels of the viewfinder small enough so that your eye couldn't tell the difference between looking through it or a pentaprism viewfinder.

Here are some pros that I can see:
1. No mirror to design lenses around. The lens can come up as close to the sensor as you'd like. I'm not an optical engineer, so I don't know how much of a constraint it actually is.
2. No prism. This should cut down on weight and perhaps size (I guess it depends on what the optics for the EVF look like before you can actually say either size or weight will improve).
3. More versatile camera status display. I'm currently annoyed that on my D90, I have to choose whether to have either the number of pictures remaining on the card or the ISO in the viewfinder. I choose ISO, but it would be nice to have complete customization of what's displayed in the viewfinder, including a real-time histogram to help with exposure (I almost exclusively shoot manual and watch the meter, but a live histogram would be so much more useful to me than the segmented meter display). You could also have it display in B&W but simulate different color filters for B&W photography.
4. More extensible (if that's the word I'm looking for). Imagine having something like that Nikon UP300x that has an eyepiece that could display your EVF image while you point the camera however and wherever you want. I'm guessing that would be sweet for photojournalism. I'd love it for weddings, even though it would make me look like a cyborg wedding photographer. For someone who mods their camera to shoot IR, it could also double as a night vision scope.
5. 100% accurate viewfinder frame coverage. No more guessing at how much of the edge is missing from your VF image (I know some cameras have 100%, but every camera with an EVF would).
6. Takes advantage of sensor's amplification circuitry. I'd rather not have around half of the light lost from bouncing around in the prism. I'd love to be able to see in the dark, which is about what you can do with the ridiculously high ISO sensitivities available these days. Besides, you could amplify it for the EVF but shoot at a lower ISO if, for example, you were going to shoot a long exposure.

and the cons:
1. No phase-detected autofocus. Yikes! Is this enough to kill the idea? I can't see a way to overcome this since as I understand it you actually need a prism between the lens and the sensor to do phase AF. Someone brilliant may prove me wrong, though, and there might be a way to improve the contrast AF algorithms or speed up the processors running them to get AF times to an acceptable level. Alternatives could be some other type of ranging--maybe infrared laser or ultrasonic pulses (hey, laser ranging works for golf caddies, right?). I'm imagining a touch screen under my left thumb that lets me tell the camera where to focus, while the camera tracks that location and superposes a small box on the image in the EVF that changes color when it's focused.
2. Sensor overheating and battery life issues. These could be overcome by improving the efficiency of the sensor's circuits, but for now heating is a problem--you can actually feel the D90 or the D300 heating up in live view mode.
3. Not completely real-time. Imagine the rolling shutter (jello) effect in your viewfinder. On second thought, don't, it's making me dizzy. Could this also be fixed, maybe alongside improvements to the video of newer cameras?

Does anyone have any other pros or cons? You can also call me a looney, but I'm convinced that someday (maybe soon) it will be an option.